Grate-bar



TQ-M7255.

NFETEHS. PHOTO UTHOGHAP WASHINGTON, D. C.

UNITED STATES PATENT OEEIoE.

sAM'iIEL HARRISON, 0E PHILADELPHIA, PENNSYLVANIA.

GRATE-BAR.

Specification forming part of Letters Patent No. 58,252, dated September 25, 1866.

To all whom it may concern:

Be it known that I, SAMUEL HARRISON, of Philadelphia, Pennsylvania, have invented an Improved Grate-Bar for Boiler and other Furnaces; and I do hereby declare the following to be a full, clear, and exact description of the same, reference being had to the accompany ing drawings, and to the letters of reference marked thereon.

My invention relates to an improvement in that class of grate-bars which consist of a number or group of ribs cast together with spaces between the ribs; and my improved grate-bar consists of a deep and shallow rib or ribs combined in one casting, substantially as described hereainfter, so thatthebar may be more easily molded Vand cast, may afford a better circulat-ion of air between the ribs, may be less liable to be choked with cinders and slag, and lighter, and consequently more economical, than ordinary grate-bars having a number of ribs of uniform depth.

In order to enable others skilled in the art to make and use my invention, I will now proceed to describe several modes in which it may be carried out.

On reference to the accompanying d1awings, which form a part of this specification, Figure l is a side view of my improved gratebar 5 Fig. 2, a plan view; Fig. 3, a transverse section on the line `l 2, Fig. l; Fig. 4, an end view; Fig. 5, a diagram, illustrating one of the advantages of my invention', Fig. 6, an end view of two bars resting on a bearing; Figs. 7, 8, 9, and 10,1nodiiications of my irnproved grate-bar.

Similar letters refer to similar parts-thro u ghout the several views.

On reference to Figs. l, 2, 3, 4, and 6, A is the bar, which, in the present instance, is composed of the three ribs, a, c', and a", connected together at the opposite ends by webs b l), and at suitable intermediate points by webs d, d', and @,the whole being cast in one piece.

The outside ribs, a and a, are much shallower than the middle rib, and, as seen in Fig. l, are made in the form of an arch on the under side. They may, however, be straight, or of the form shown in Fig. 10.

` The middle rib is made much deeper than the outer ribs, and is made in the form of an inverted arch. I

The ribs a., a', and a are arranged at a proper distance apart to snit the fuel which has to be used iu the furnace, of which anumber of these bars form the grate, and on the exterior of the outer ribs, a and a, are the usual projections f, by means of which the bars are maintained at a proper distance apart from each other.

The advantages of my improved grate-bar may be enumerated and described as follows:

First, they can be molded and cast with greater facility than ordinary bars, in which a number of ribs of uniform depth are cast together. This will be readily understood by reference to the diagram, Fig. 5, which illustrates the impression in the sand made by a pattern of my improved bar. The walls y y of sand between the ribs being much more substantial than if the ribs were Iol" uniform depth, there is consequently less danger of bad castings, as well as less manipulation required in dressing and finishing the mold.

Second, there will be a more free circulation of air through the spaces between the ribs of my improved bar than through bars having ribs of uniform depth, as the air has to pass through much shallower openings in the former than inthe latter case. (See arrows, Fig. 3.)

Third, there is less liability of the spaces between the ribs becoming choked with slag and cinders, as will be readily understood without explanation.

Fourth, the intermediate rib a of the form shown imparts the desired vertical rigidity to the bar; hence the outer ribs may be of the reduced depth illustrated-and described, there# `by effecting a corresponding reduction in the weight of the bar and a saving of material.

Although I prefer in ordinarycases a bar composed of three ribs, as described above7 bars with five ribs, as seen in Fig. 6, or with six ribs, as shown in Fig. 7, or even with two ribs, as illustrated in Fig. 8, may be made and used with good results.

It will be seen on reference to Figs l and 6 that the outer ribs at each end of the bar pro ject below the middle rib, the outer ribs only' first, n more s'eady bearing is afforded to the A gra-tebar consisting of :L deep and sha-lbars than if the whole of the ribs rested on low rib or ribs Combined in one casting, subthe bearers; second, openings t t, Fig. 6, are stantially as and for the purpose set forth.

presented for the free passage of air in the In testimony whereof I have signedmy name direction pointed out by Jche arrows, Fig. l. to this specification in the presence of two Wvitliout confining myself to any speeio subscribing Witnesses.

number of deep and shallow ribs, or to the SAML. HARRISON.

preeisevform of these ribs, I claim as my in- Witnesses:.

Vention and desire to secure by Letters Patv H. HOWsoN,

ent J OIIN WHITE. 

